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Identification of pathologic parathyroid glands in primary hyperparathyroidism, traditionally based on neck ultrasound (US) and/or 99mTc-Sestamibi scintigraphy, can be challenging. PET/CT with 18F-Fluorocholine (18F-FCH) might improve the detection of pathologic parathyroid glands. We aimed at comparing the diagnostic performance of 18F-FCH-PET/CT with that of dual-phase dual-isotope parathyroid scintigraphy and neck US. Thirty-four consecutive patients with primary hyperparathyroidism were prospectively enrolled, 7 had normocalcemic hyperparathyroidism, and 27 had classic hypercalcemic hyperparathyroidism. All patients underwent high-resolution neck US, dual-phase dual-isotope 99mTc-Pertechnetate/99mTc-Sestamibi scintigraphy, and 18F-FCH-PET/CT. In the whole patients’ group, the detection rates of the abnormal parathyroid gland were 68% for neck US, 71% for 18F-FCH-PET/CT, and only 15% for 99mTc-Sestamibi scintigraphy. The corresponding figures in normocalcemic and hypercalcemic hyperparathyroidism were 57 and 70% for neck US, 70 and 71% for 18F-FCH-PET/CT, and 0 and 18% for 99mTc-Sestamibi scintigraphy, respectively. In the 17 patients in whom the abnormal parathyroid gland was identified, either at surgery or at fine needle aspiration cytology/biochemistry, the correct detection rate was 82% for neck US, 89% for 18F-FCH-PET/CT, and only 17% for 99mTc-Sestamibi scintigraphy. 18F-FCH-PET/CT can be considered a first-line imaging technique for the identification of pathologic parathyroid glands in patients with normocalcemic and hypercalcemic hyperparathyroidism, even when the parathyroid volume is small.

El cáncer de próstata (CaP) representa el tumor maligno más frecuente en los varones, pero según las directrices de la European Association of Urology(EAU) no deben realizarse cribados masivos para el diagnóstico de CaP debido a problemas relacionados con el sobrediagnóstico y sobretratamiento. El diagnóstico clínico precoz es posible, principalmente basado en el tacto rectal y la determinación del antígeno prostático específico (PSA). Sin embargo, el único test que puede determinar la presencia de un CaP es la biopsia guiada por ecografía, obteniendo múltiples muestras, la cual tiene un elevado valor pronóstico. En este contexto, la imagen diagnóstica juega un importante papel tal como lo confirmó la EAU, que en una actualización de 2016 de su guía clínica sobre CaP estableció la importancia de la tomografía por emisión de positrones (PET) con 11C- o 18F-colina combinada con la tomografía computarizada (TC) para individualizar la recidiva local, la afectación de ganglios linfáticos y la diseminación metastásica en todos los estadios. En consecuencia, en 2017, la European Association of Nuclear Medicine(EANM) junto con la Society of Nuclear Medicine and Molecular Imaging(SNMMI) compartieron nuevas directrices para la PET/TC con 68Ga-antígeno de membrana prostático específico (PSMA) para ayudar a los médicos en la recomendación, realización e interpretación de los estudios PET/TC en pacientes con CaP. De esta manera, el objetivo de este «artículo de evidencia» es definir el algoritmo diagnóstico actual en el CaP para incrementar el nivel de confianza global en el enfoque de un tema tan crucial.

Inflammatory bowel diseases (IBD) are a group of pathological conditions characterized by chronic inflammation of the gastrointestinal tract, including Crohn's disease and ulcerative colitis. To date, imaging of IBD is based on several radiological techniques such as barium studies, magnetic resonance imaging, and computed tomography (CT). Endoscopy is the gold standard for the assessment of the large bowel and proximal small intestine in patients with IBD allowing the biopsy of the visualized bowel. Positron emission tomography (PET) and PET/CT with Fluorine-18-fluoro-2-deoxy-D-glucose (FDG) is a functional imaging method used to detect abnormalities in glucose metabolism in a variety of disorders. FDG accumulates mainly in tumours, but increased uptake and retention has been shown also in lesions with a high concentration of inflammatory cells, such as granulocytes and activated macrophages. Recent literature data demonstrate that FDG-PET and PET/CT may be useful noninvasive tools for identifying and localizing active IBD. In patients with an established diagnosis of IBD, FDG-PET and PET/CT may provide information about disease activity, location and extent of the disease within the intestinal tract, allowing early recognition of disease relapse and possible complications. Furthermore, these techniques may play a role in assessing the treatment response to medical therapy in patients with IBD.

Abstract: Transient osteoporosis is an infrequent condition of uncertain etiology with pain, limited range of motion and radiographic evidence of osteoporosis affecting one or more joints. It is self-limited, reversible and can involve only the hip (transient osteoporosis of the hip, TOH) or, less frequently, one or more joints contemporaneously or at different times (regional migratory osteoporosis, RMO). We studied four men with transient osteoporosis, including two with TOH and two with RMO. All patients underwent a standard radiographic work-up of the affected joints, arteriovenous Doppler US, computed tomography, magnetic resonance imaging (MRI) and three-phase bone scanning. In all patients, symptoms were related to bone marrow edema demonstrated at MRI and to a transitory regional arterial hyperflow observed at the early scintigraphic analysis. On the basis of our observations, we hypothesize that regional arterial hyperflow may be the cause of the bone marrow edema and therefore of the transient osteoporosis.

Myocardial uptake of 99Tcm-tetrofosmin in vivois determined by a combination of flow and metabolic status of myocytes. The accumulation of tetrofosmin in the mitochondria is related to their ability to transduce metabolic energy into electronegative membrane potential. Trimetazidine (TMZ), an anti-ischaemic drug, appears to have a metabolic cytoprotective effect related to mitochondrial function, since it does not induce systemic or coronary haemodynamic changes. In this study, we evaluated the effects of TMZ on tetrofosmin uptake in hypoperfused myocardial regions in patients with coronary artery disease (CAD). Twenty-two patients, 14 with previous myocardial infarction (group A) and eight with a history of angina (group B), with angiographically documented CAD were studied. All patients underwent two tetrofosmin SPET studies at rest, before (baseline) and 1 week after TMZ administration (post-TMZ). On quantitative analysis, 131 segments showed less tetrofosmin uptake at baseline. In these segments, tetrofosmin uptake was 51±13 at baseline and 55±15 post-TMZ (P<0.001 vscontrol). In the 86 hypoperfused segments of group A, tetrofosmin uptake was 48±14 at baseline and 52±17 post-TMZ (P<0.001 vscontrol). In the 45 hypoperfused segments of group B, tetrofosmin uptake was 56±9 at baseline and 60±10 post-TMZ (P<0.001 vscontrol). In the remaining 309 segments, no significant difference in tetrofosmin uptake before and after TMZ was observed. In conclusion, our results suggest that TMZ administration may increase myocardial uptake of tetrofosmin in hypoperfused regions at rest in patients with CAD, based on its metabolic effect.

Twenty patients with known ovarian cancer have been investigated in this pilot study to verify the clinical usefulness of radioimaging using the B72.3 monoclonal antibody labelled with iodine-131. No adverse reactions occurred after intravenous injection of B72.3 MoAb. The radioimaging results were compared with those obtained with other diagnostic methods, including computed X-ray tomography and ultrasound. A sensitivity of 85 in the detection of primary ovarian cancers and collections of ascites, and of 84 in the detection of abdominal and extraperitoneal metastases has been demonstrated using this radioiodinated antibody in vivo. No false localization occurred. Immunohistochemical studies showed no cross-reactions between B72.3 MoAb and mesothelial cells, confirming the high specificity of binding between B72.3 MoAb and neoplastic cells in ascites. Negligible uptake of radiolabelled B72.3 MoAb has been demonstrated in the unaffected ovary. The major advantage of using this monoclonal antibody is related to the expression of a recognized antigen (called TAG 72) in mucinous, serous and in differentiated denocarcinomas of the ovary.

Septic sacroiliitis in childhood is a relatively rare condition. We describe a case of septic sacroiliitis occurring in an 11-year-old girl in whom the diagnosis was suspected on clinical findings and bone scan. Immunoscintigraphy with99mTc-labelled antigranulocyte antibodies further supported the hypothesis for a septic origin of the disease. The clinical evolution cliniched the diagnosis.

To evaluate alterations induced by injectedmurine radiolabelled F(ab’)2fragments of the anti HMW-MAA MoAb 225.28S on the principal haemato-immunological parameters, 32 patients with advanced malignant melanoma were studied. No statistically significant change was found after MoAb administration, but monocytes (3h after injection) and granular eosinophils (24 h after) were reduced and circulating immune complexes increased (3 h after). No toxic effect or adverse reaction was observed.Therefore, the controlled administration of purified MoAb fragments for diagnostic purposes seems to involve only a very low risk of immediate adverse reactions

We previously reported generalized cerebral glucose hypometabolism in amyotrophic lateral sclerosis (ALS) patients with upper motor neuron disease, using positron emission tomography (PET) with [18F]2-fluoro-2-deoxy-D-glucose. The present article presents a more detailed regional analysis of the hypometabolism, including measurements of the motor-sensory cortex at higher levels than used earlier. The analysis is based on 19 PET studies of 12 patients with ALS, four of whom had only lower motor neuron involvement, and 11 studies of age-matched control subjects. A brain size correction was included to eliminate differences in metabolism related to brain size but not to pathology. The eight ALS patients with both upper and lower motor neuron disease showed generalized hypometabolism, compared with the normal control subjects, that was greatest in the motor-sensory cortex and putamen. The motor-sensory deficit was strongly correlated with length of disease, and a marked sequential reduction was seen in repeat studies on four of the patients. There was also significant right-left asymmetry in these scans. No cerebral hypometabolism was seen in the four ALS patients without upper motor neuron involvement. Although the observed motor-sensory deficit in ALS is consistent with histopathological findings, the more generalized hypometabolism and the asymmetry suggest more widespread effects.

A 59-year-old man is reported, who became aphasic after left thalamic infarction, shown by CT. His speech was fluent, with reduced voice volume, impaired auditory and reading comprehension, verbal paraphasias but intact repetition skills. A single photon emission computed tomography (SPECT) scan to measure regional cerebral flow (rCBF) showed a reduction of flow in the parietotemporal areas of the left hemisphere. It is suggested that thalamic aphasia could result from structural subcortical damage with a homolateral functional cortical deficit leading to the specific aphasic disturbance.

In a 28-year-old man with Cushing's syndrome, studies investigating a hypophyseal and/or adrenal origin of the disease, including computed tomography and magnetic resonance imaging, were negative. In agreement with reports showing somatostatin receptors on the cell membrane of ectopically secreting ACTH tumours, scintigraphy was performed after intravenous injection of 111 MBq 111In-pentetreotide (OCT). The radiolabelled OCT scan showed a small focal area of intense uptake at the inferior lobe of the right lung. Subsequent radioguided surgery located and defined a small mass (1.8 x 1.4 x 1.6 cm). The probe pinpointed the mass to the right inferior chest lobe, with a tumour/normal tissue count ratio of 6:1 and tumour/hilar normal lymph node ratio of 12:1, thus permitting the complete excision of the tumour to exclude lymph node and/or parietal involvement. A lung carcinoid was diagnosed at histology. The patient is still alive and disease-free 24 months after surgery. 111In-OCT was found to be useful for localizing the ACTH-secreting tumour and also permitted rapid non-invasive differential diagnosis between an ACTH-secreting pituitary adenoma and malignancy causing ectopic ACTH syndrome. This study also showed the clinical usefulness of radioguided surgery in the treatment of bronchial carcinoid.